Five people have been killed after a bomb exploded in Damascus on Tuesday, following pre-dawn raids by security forces in the Syrian capital.

The device was detonated in a restaurant in the Qaboun neighborhood, a hot-bed of protests against President Bashar al-Assad.

The bloodshed came as U.N. Secretary General Ban Ki-Moon warned that Syria was approaching a pivotal moment as the country slides into all-out civil war.

State media blamed terrorists -- a generic term for any anti-Assad forces -- for Tuesday's blast, while opposition forces and activist groups have not yet claimed responsibility.

According to the Syrian Observatory for Human Rights, a British-based opposition group, the bomb detonated around midnight.

The restaurant blast brings the total number of people killed on Monday to 59, according to the Observatory.

The ongoing bloodshed, which has steadily escalated for the past 14-months, comes despite a promised ceasefire and the presence of a U.N. observer force on the ground trying to monitor the situation.

On Monday, fighting between rebels and government forces was reported in the northwestern town of Kfar Roma, while the human rights group also said there were explosions overnight in several other areas including Hama, northern Aleppo and the coastal cities of Banias and Latakia.

There were also reports of dozens of arrests during pre-dawn raids in the capital.